The disclosure relates to thermoelectric materials prepared by self-propagating high temperature synthesis (SHS) process combining with Plasma activated sintering and methods for preparing thereof. More specifically, the present disclosure relates to the new criterion for combustion synthesis and the method for preparing the thermoelectric materials which meet the new criterion.

A method of heat-treating for a metal molded article includes: a shape holding layer formation step of forming on a shape holding layer having a melting point higher than a solidus temperature Ts of a composition of the metal molded article on a surface of the metal molded article by treating the metal molded article; and a first heat-treatment step of performing a first heat treatment on the metal molded article at a first temperature T1, after forming the shape holding layer. When a reference temperature Ta is a temperature lower than the solidus temperature Ts by 100 C., and Tm is the melting point of the shape holding layer, the shape holding layer formation step and the first heat-treatment step are performed so as to satisfy an expression TaT1Tm.

A method of heat-treating for a metal molded article includes: a shape holding layer formation step of forming on a shape holding layer having a melting point higher than a solidus temperature Ts of a composition of the metal molded article on a surface of the metal molded article by treating the metal molded article; and a first heat-treatment step of performing a first heat treatment on the metal molded article at a first temperature T1, after forming the shape holding layer. When a reference temperature Ta is a temperature lower than the solidus temperature Ts by 100 C., and Tm is the melting point of the shape holding layer, the shape holding layer formation step and the first heat-treatment step are performed so as to satisfy an expression TaT1Tm.

Devices comprising a component which has an open porous structure composed of an alloy of nickel and titanium or a mixture of nickel and titanium. The devices can be implanted in a mammalian body and provide desired interaction with protein, blood, ions, bone cells, and tissue. The devices are particularly useful for providing a substrate for the ingrowth of bone. In the open pore structure, preferably more than 95% of the pores having a size of 50-1000 m, particularly 50-600 m, with a pore size standard deviation of 250 m or less, particularly of 150 m or less, and an average porosity by volume of 40-80%. When the device is implanted adjacent to a cancellous bone, the porous component preferably has a modulus of 0.1-1.2 GPa. When the device is implanted adjacent to cortical bone, the porous component preferably has a modulus of 16 to 24 GPa. The devices are also useful for filtering a liquid.

A process for preparing alloy products is described using a self-sustaining or self-propagating SHS-type combustion process with point-source ignition, preferably a laser, in a pressurized vessel. Binary, ternary and quaternary alloys can be formed with control over polycrystalline structure and bandgap. Methods to tune the bandgap and the alloys formed are described. The alloy products may be doped. Preferably sulfides, tellurides or selenides are formed. Cooling during reaction takes place.

A process for preparing alloy products is described using a self-sustaining or self-propagating SHS-type combustion process with point-source ignition, preferably a laser, in a pressurized vessel. Binary, ternary and quaternary alloys can be formed with control over polycrystalline structure and bandgap. Methods to tune the bandgap and the alloys formed are described. The alloy products may be doped. Preferably sulfides, tellurides or selenides are formed. Cooling during reaction takes place.

Articles are manufactured using self-propagating high-temperature synthesis (SHS) reactions. Particulates including reactants can be blended to form a particulate blend. The particulate blend can be preformed. The preform article can be heated to a pre-heat temperature being below an auto-activation temperature and above a minimum compression activated synthesis temperature. Compressive stress can be exerted on the preform article at the pre-heat temperature to initiate the SHS reaction between the reactants and thereby form a product metallic compound. At approximately peak temperature, a flow stress of the product metallic compound can be exceeded to substantially reduce porosity and thereby form a shaped substantially dense article.

Articles are manufactured using self-propagating high-temperature synthesis (SHS) reactions. Particulates including reactants can be blended to form a particulate blend. The particulate blend can be preformed. The preform article can be heated to a pre-heat temperature being below an auto-activation temperature and above a minimum compression activated synthesis temperature. Compressive stress can be exerted on the preform article at the pre-heat temperature to initiate the SHS reaction between the reactants and thereby form a product metallic compound. At approximately peak temperature, a flow stress of the product metallic compound can be exceeded to substantially reduce porosity and thereby form a shaped substantially dense article.

Articles are manufactured using self-propagating high-temperature synthesis (SHS) reactions. Particulates including reactants can be blended to form a particulate blend. The particulate blend can be preformed. The preform article can be heated to a pre-heat temperature being below an auto-activation temperature and above a minimum compression activated synthesis temperature. Compressive stress can be exerted on the preform article at the pre-heat temperature to initiate the SHS reaction between the reactants and thereby form a product metallic compound. At approximately peak temperature, a flow stress of the product metallic compound can be exceeded to substantially reduce porosity and thereby form a shaped substantially dense article.

Metallic matrix composites include a high strength titanium aluminide alloy matrix and an in situ formed aluminum oxide reinforcement. The atomic percentage of aluminum in the titanium aluminide alloy matrix can vary from 40% to 48%. Included are methods of making the metallic matrix composites, in particular, through the performance of an exothermic chemical reaction. The metallic matrix composites can exhibit low porosity.